Two years ago, Google said its Street View cars had been “harvesting” information from Wi-Fi networks, including personal home networks, as a matter of course.

In some cases, data gathered included passwords, e-mail messages and browser information.

The data gathering was accidental. Google as an organization didn’t mean to collect this information. But even if it had meant to, there would be nothing wrong with doing so. I’ll tell you why later.

The FCC did charge Google a pathetic $25,000 fine for taking too long to respond to requests for information during the investigation. But it didn’t levy any fine for the actual data harvesting. Inconvenient truth: In a country ruled by law, you can’t legally punish people or companies when they haven’t in fact broken an actual law.

Still, critics are coming out of the woodwork to denounce both Google and the FCC.

And as they tend to do in such cases, the pandering politicians are trying to get in front of the parade.

For example, U.S. Rep. Edward J. Markey (D-Mass.) this week issued a statement that says “The circumstances surrounding Google’s surreptitious siphoning of personal information leave many unanswered questions. I believe Congress should immediately hold a hearing to get to the bottom of this serious situation.”

Other countries, including Germany, France and Australia, concluded (unlike the FCC) that Google was guilty of wrongdoing.

Australian Minister for Communications Stephen Conroy called the it the ” largest privacy breach in the history across western democracies.” The Australian government forced Google to publicly apologize.

France made Google pay a $142,000 fine.

The global consensus is that Google’s so-called “snooping” was an invasion of privacy, accidental or otherwise.

Unfortunately, this consensus is based on emotion and knee-jerk populism, rather than facts and reason.

Let’s try something different. Let’s analyze what actually happened.

Wi-Fi is radio broadcast over the public airwaves

The hyperbolic accusations against Google imply that the company electronically reached into people’s homes, breached their Wi-Fi systems, took data and stored it in a database.

That’s not what happened.

Google did not harvest data from inside people’s homes. Google plucked data from the public airwaves — data that was voluntarily broadcast into those airwaves by the owners of that data.

In the U.S., the airwaves belong to the public.

Wi-Fi devices that people use for home networking have radios built in. And it’s via radio waves that the miracle of wireless networking takes place.

A home Wi-Fi device generates radio waves that are sent out in 360 degrees, like the ripples that radiate across the surface of a pond when you throw a rock into it. These radio waves go right through the walls of the house, and out into the world at high speed.

At some point in their journey, Wi-Fi radio waves breach the private-public barrier. They wash over your privately owned lawn before continuing on over the publicly owned sidewalk and street.

A person walking or driving by is physically penetrated by these waves. (Some studies have suggested that the waves may increase the risk of cancer; they probably don’t.) The radio waves enter people’s bodies, are conveyed through their bodies, and then continue on their journey on the other side.

Wi-Fi radio waves also trespass onto other peoples’ private property. If your laptop can see the name of your neighbor’s Wi-Fi, that means he is broadcasting radio waves over your property line, through the walls of your house and into your home.

What’s interesting about this broadcasting of electromagnetic radiation is that it’s nothing new. People do it all the time with other parts of the electromagnetic spectrum.

Shining light on Wi-Fi ‘snooping’

Let’s say you took your big-screen TV and put it in your home’s front window facing out so that people could see the screen from the sidewalk or the street.

Then let’s say you connected your laptop to it, then made a PowerPoint slide so that in large letters, the TV displayed the following phrase: “My password is bond007.”

If anyone, whether Google or your neighbor, stood on the sidewalk and took a picture of your house, they would be recording your password. And this would be, and should be, perfectly legal.

There are two reasons why this is legal. First, the recording happened from a public space. And second, the recording was made with a device in general public use — a camera.

Any outrage expressed by the person broadcasting his password via electromagnetic radiation (light) into the public space would be ludicrous.

In fact, there are many ways to use electromagnetic radiation to broadcast personal data into the public airwaves.

One could say “My password is bond007″ into a walkie-talkie, a ham radio or a CB radio.

It’s perfectly legal for a passerby or anyone else to listen to and record that audio signal, as long as he’s in a public space or in his own home.

Even if the broadcaster is ignorant of the fact that speaking into a radio conveys his voice into the public space, it’s still not illegal for someone else to listen to it or record it.

In each of these cases — the TV in the window, the walkie-talkie, the ham radio or the CB radio — the data is being broadcast via electromagnetic radiation out into the public airwaves and therefore it is not a violation of privacy for someone else to receive and record the data.

A Wi-Fi signal is exactly the same thing. It uses electromagnetic radiation to broadcast data into the public airwaves.

As in my thought-experiment, it’s up to the owner of the equipment to determine whether and what data is broadcast publicly.

When someone sets up a Wi-Fi network and a Google Street View car drives by and captures the data, it’s not that Google is invading the home. The Wi-Fi signal is invading the Street View car on a public road.

I believe the burden is on anyone who says Google’s data harvesting is illegal to explain why recording data voluntarily broadcast into publicly owned airwaves over one part of the electromagnetic spectrum is legal, but doing so over another part of the spectrum is illegal.

What’s the difference?

It’s not as if the equipment that’s needed to view and record such data is hard to find. You can buy it at Wal-Mart, and nearly everyone owns such equipment.

Look, Wi-Fi is no longer some new, mysterious and rare phenomenon. It’s not witchcraft, or some unknown to be feared and confused about.

I think we can all agree that anyone who broadcasts unencrypted, un-password-protected data over public airwaves in a way that is readable by devices millions of people own has no reasonable expectation of privacy.

And anyone who views, records or “harvests” such publicly broadcast data has — and should have — every right to do so. The hysteria around the so-called Google “WiSpy” scandal represents an ignorant double standard about data voluntarily broadcast over public airspace.